According to conventional art, for example, the scroll fluid machine disclosed in Japanese Patent Application Publication (Kokai) No. 2003-129970 is so configured that a spiral-shaped orbiting wrap formed in an orbiting scroll is meshed with a spiral-shaped fixed wrap formed in a fixed scroll. The orbiting scroll is brought into an orbital motion to draw fluid from an inlet located on a radially outward side. A compression space into which the fluid is drawn is gradually decreased in size toward the center side, and thus the fluid is compressed. The compressed fluid is discharged from an outlet located on the center side. This scroll fluid machine includes a compression chamber divided into two stages, namely, a first-stage compression chamber located on the radially outward side and a second-stage compression chamber on the radially inward side. A first-stage outlet formed in the terminal end of the first-stage compression chamber and a second-stage inlet in communication with the drawing space of the second-stage compression chamber are piped together via a cooling device. The compressed fluid that has been compressed in the first-stage compression chamber is discharged from the first-stage outlet, refrigerated by passing through the cooling device, guided into the second-stage compression chamber through the second-stage inlet, and then compressed again. This prevents the heat generated by fluid compression from decreasing the life of the bearings and the seal members fitted in wrap grooves formed in the tips of wraps.
According to the invention illustrated in FIG. 2 of Japanese Patent Application Publication (Kokai) No. 2003-129970, the seal member includes a spiral-shaped first seal member fitted in the wrap groove and an intermediate seal member disposed between the first-stage outlet and the second-stage inlet. The intermediate seal member prevents compressed gas from escaping from the second-stage compression chamber side into the first-stage compression chamber side.
According to the invention illustrated in FIGS. 6 to 9 of the same publication, the seal member includes first and second seal members. The first seal member is arranged into a spiral which extends from the fluid-drawing side on the first-stage compression chamber side toward the outlet side of the second-stage compression chamber. The first seal member partitions the first-stage outlet from the second-stage inlet in between the first-stage and second-stage compression chambers. The second seal member includes an end which is in contact with the first seal member on the surface opposite to the inlet opening in proximity to the outlet opening. The second seal member stretches from the proximity of the outlet opening, extends around the second-stage compression chamber, reaches the proximity of the outlet opening, then comes into contact with the first seal member on the surface opposite to the outlet opening.